Braille communication terminal

ABSTRACT

A Braille Telecommunications Terminal is described herein which is adapted to emboss complete lines of braille characters at high speed in response to code characters received by the terminal from a communications line or from a keyboard in the terminal. A plurality of pairs of pins are disposed in a row and are actuable to move forward to an extended position against an embossable sheet to form pairs of code elements of the characters in a line of braille characters. The sheet is advanced and successive pairs of code elements are embossed upon each advance until the code elements which constitute the braille characters are embossed. In this manner an entire line of braille characters can be embossed at very high speeds. The pins and the advancing of the sheet are automatically controlled in response to code signals received by the terminal, or from the keyboard.

United States Patent [191 Carbonneau 1 Apr. 29, 1975 BRAILLECOMMUNICATION TERMINAL [75] Inventor: Guy P. Carbonneau, West Henrietta,NY.

[22] Filed: Sept. 4, 1973 [21] Appl. No.: 394,328

[52] US. Cl. 197/6.1; 101/18; 340/173 RC [51] Int. Cl B41j 3/32 [58]Field of Search 197/1 R, 6, 6.1, 19;

178/92; 340/173 RC, 172.5; 101/3 R, 26, 28-32, 18; 61/93 C [56]References Cited UNITED STATES PATENTS 2,565,608 8/1951 Hoff 101/3 R3.065.299 11/1962 Frey 178/92 3,174,427 3/1965 Taylor 101/93 C 3,453,6487/1969 Stegenga 1 197/1 R X 3,534,846 10/1970 Watari 197/6.1 3,611,30810/1971 Grinnell 197/19 X 3,640,368 2/1972 Weinberger 197/6.1

FOREIGN PATENTS OR APPLICATIONS 580,809 8/1958 ltaly 197/6.1

OTHER PUBLICATIONS Powered Braille Typing System," IBM Tech. Discl.Bulletin, Vol. 12, No.6, 11/69, p. 779

Automatic Braillewriter, IBM Tech. Discl. Bulletin, Vol. 10, No. 11,4/68, pp. 177l-3 Embossing Braille Characters," IBM Tech. Disc].Bulletin, Vol. 8, No. 10, 3/66, pp. 1424 High Speed Embossing ofBraillemasters," IBM Tech. Discl. Bulletin, Vol. 11, No. 10, 3/69, pp.l2967.

Primary Examiner-E. H. Eickholt Attorney, Agent, or Firm-Martin LuKacher[57] ABSTRACT A Braille Telecommunications Terminal is described hereinwhich is adapted to emboss complete lines of braille characters at highspeed in response to code characters received by the terminal from acommunications line or from a keyboard in the terminal. A plurality ofpairs of pins are disposed in a row and are actuable to move forward toan extended position against an embossable sheet to form pairs of codeelements of the characters in a line of braille characters. The sheet isadvanced and successive pairs of code elements are embossed upon eachadvance until the code elements which constitute the braille charactersare embossed. In this manner an entire line of braille characters can beembossed at very high speeds. The pins and the advancing of the sheetare automatically controlled in response to code signals received by theterminal, or from the keyboard.

20 Claims, 10 Drawing Figures PATENTEZ Z 3. 880,269

sum 2 0r 6 SECOND ROW OF IMPRESSIONS THIRD ROW OF IMPRESSIONS DOUBLESPACED FOR FIRST ROW OF NEXT ROW OF IMPRESSIONS FIGAC.

MTEMEEAFRZSEIE 3.880.269

' sum u 0F 6 SERIAL DATA FROM COMMUNlCATlON LINE AND 340 OR AND 33SERIAL LOAD GND

FIGAA. FIGAA. FIGAB.

PiiEf-flEmFazsims 3.880.269

SHEET 5 BF 6 AND 408 EMBOSS CYCLE FLIP FLOP AND AND AND AND AND AND 414I56 AND AND RESET A 5 FIGAB.

BUFFER I59 FULL BRAILLE COMMUNICATION TERMINAL TI-IE FIELD OF THEINVENTION This invention relates to braille communications ter minalsand particularly to an improved system for embossing braille charactersat very high speed.

BACKGROUND OF THE INVENTION There have heretofore been provided brailletypewriters which are of a complex mechanical design thus making themrelatively slow, noisy and expensive. Such braille typewriters areoperative to emboss one braille character at a time. much in the samemanner as a conventional typewriter which types alpha-numericcharacters. Thus conventional braille typewriters are limited in speedof operation in that they are bound by the inherent limitations of thespeed of their moving parts. Moreover, conventional braille typewritersare adapted to be manually operated and can not be operated by messagedata received from a telecommunications line or link as is the case foralpha-numeric teletypewriters and teleprinters. Thus there has not beenavailable for persons who are not sighted the same high speed andflexible communications facilities (e.g. teletypewriters andteleprinters) which are available for sighted person. It is particularlyimportant that braille information be presented at extremely high speedcompatible with the speeds at which blind person who are adept inreading braille can read braille characters. There have not been madeavailable for the benefit of blind persons. prior to the presentinvention, extremely high speed braille character embossing apparatusand particularly an apparatus which is automatically operated to receivethe same type of message data which is provided for teletypewriters andteleprinters for embossing braille characters at high speeds a line at atime.

OBJECTS AND SUMMARY OF THE INVENTION It is therefore an object of thepresent invention to provide improved apparatus for braillecommunications.

It is another object of the present invention to provide improvedbraille embossing apparatus which is capable of embossing braillecharacters a line at a time using message data of the type which isavailable and used conventionally for digital telecommunicationsapplications.

It is a still further object of the present invention to provide animproved braille typewriter which is also operative as a brailleteletypewriter when coded signals are applied thereto via a transmissionline or other communications channel or link.

It is a still further object of the present invention to provide animproved braille communications terminal which is relatively low incost.

It is a still further object of the present invention to provide animproved braille communications terminal capable of printing braillecharacters at extremely high speeds, say 120 characters per second orl80lines per minute.

It is a still further object of the present invention to provide animproved high speed braille communications terminal which is relativelyquiet.

It is a still further object of the present invention to provide animproved high speed braille communications terminal which operatesautomatically in response to received message data, translates such datainto braille characters, and enbosses a sheet with braille characterscorresponding to the received message data and advances the sheet in topermit the embossing of successive lines of the braille characters.

Briefly described, a braille communications terminal involving theinvention includes a row of embossing members for embossing thecollinearly disposed elements of a line of braille code characters allat the same time. Each braille code character consists of three pairs ofcode elements disposed one below the other. or six code elements in all.In accordance with this invention a line of braille characters isembossed by successively embossing the pairs of code elements whichconstitute a line of braille characters all at the same time. Thesheet-which is adapted to receive the embossing is advanced so that thesecond pair of code elements of the line of characters is embossed. Thenthe sheet is advanced a third time until the third pair of code elementsis embossed. In this way entire lines of braille code characters isadapted to be embossed at extremely high speed. The communicationsterminal includes a system of electronic circuits such as registers,memories, gates. flip-flops, and sources of timing signals, all of whichare responsive to the code signals of the data characters to be embossedin the from of braille characters for successively operating theembossing apparatus so that successive lines of the braille charactersare embossed, and the sheet on which the characters are embossed isautomatically advanced.

The foregoing and other objects and advantages of the present inventionwill be more readily understood from the following detailed descriptionof an illustrative embodiment of the invention shown in the accompanyingdrawings. in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a partially broken away topview of a braille FIGS. la. 1b, and 1c are fragmentary plan views of theportion of the structure shown in FIG. 1 which illustrates the operationof the appratus in embossing rows containing successive pairs ofsuccessive lines of braille characters so as to emboss such successivelines at very high speed.

FIG. 2 is fragmentary sectional view of the apparatus shown in FIG. 1,the section being taken along the line 22 in FIG. 1;

FIG. 3 is a fragmentary sectional view showing the embossing pins of theapparatus in greater detail, the section being taken along the line 33in FIG. 2;

FIGS. 4A and 4B when joined together in the manner illustrated in FIG.5, show a detailed block diagram of the electronic circuitry included inthe braille communications terminal which is provided in accordance withthe invention;

FIG. 5 is a diagram illustrating the relationship be tween FIGS. 4A and4B; and

FIG. 6 shows timing diagram which is explanatory of the operation of theelectronic circuitry shown in FIGS. 4A and 4B DETAILED DESCRIPTIONReferring more particularly to the drawings. there is shown a braillecommunications terminal or teletypewriter for embossing lines consistingof 40 braille characters per line on an embossable medium. As shown inFIGS. 1 to 3 the embossable medium is a sheet 1 of paper of the typeused in continuous computer forms. The paper has sprocket holes 2 alongits longitudinal edges which are adapted to be engaged by the pins 3 ofa tractor pin 4 mechanism (see FIG. 2) of the type used in computerprinters. The tractor 4 has a sprocket wheel 5 which is adapted to bedriven by a paper advance mechanism.

The apparatus has frame 6 on which its various parts are mounted. Theseparts are in general an embossing pin mechanism 7, an actuatingmechanism 8, a die member 9.

The embossing mechanism 7 includes 40 pairs of embossing pins P-l toP-80. Only the pair 10 P-1 and six others are shown in detail in thedrawing to simplify the illustration. The pins of these pairs P-l toP-14 are also shown in detail as is the case for the pin P-4 (see FIG.2). Each pin is a cylindrical rod having an embossing tip 17 at theupper end thereof. The embossing pins are located in holes 18 in asupport plate 19 which is mounted on the frame 6. Each pin has a hole20, a spring wire 22 held on the plate 19 by a screw 23 extends throughthe hole in the pin and biases the pin downwardly in a direction awayfrom the sheet 1 against the actuating mechanism 8. Also mounted in theplate 20, as by being screwed therein, are adjustable stop members 24.The tips 17 are adapted to enter recessed dies 25 in a die member 26which is disposed above the plate 19 and held in the position shown withthe recessed dies in alignment with the tips of the pins by a bracketmember 27.

It will be observed from FIG. 1 that the embossing pins are collinearlydisposed in a row transversely across the sheet 1. When actuated, thepins are extended upwardly into their cooperating dies 25 which aredisposed in a line with the pins in a row across the sheet 1. The tips17 of the pins thus emboss the sheet with protuberances which form thecode elements of a line of code elements in a braille character. Thepair of pins 10 form the upper pair of code elements of the firstbraille character. next pair of pins form the elements of the secondbraille character, and so forth, for the braille characters which areadapted to be embossed in a line across the sheet. The braillecharacters as in the case of the lines 28 to 33 partially shown in FIG.1 consist of three pairs of code elements which may or may not bepresent depending upon the character represented by the braille code.The pins P-l to P-40 are selectively actuated by the actuating mechanism8 so as to emboss entire lines consisting of the pairs of the braillecode elements which constitute these characters.

The actuating mechanism itself contains 40 solenoids 5-1 to S-80 whichare disposed in rows on opposite sides of the row of pins P-l to P-80.The solenoids are offset at different distances from the rows of pinsand on opposite sides of the row of pins in the interest of simplicityand compactness and for limiting the mechanical movements .so as toreduce the noise produced from the operation of the apparatus therebyrendering it more silent. The solenoids are attached as by mountingbolts 41 to the frame 6. Each solenoid has an armature 42 which has aslot 43 in the upper end thereof. One end of a link or lever 44 isdisposed in the slot 43 and is held there in position by a pin 45. Thelinks or levers 44 are of three different lengths depending upon thedistance between the solenoid and the row of pins P-l to P-80. Each lineis privotally mounted intermediate the ends thereof at a fulcrum 46provided by a set screw 47. The fulcrums 46 are disposed at differentpositions depending upon the length of their respective levers. The topedge of the forward end 49 of each link 44 is disposed below the bottomof a different one of the pins P-l to P-80. The armatures 42 of each ofthe solenoids are biased by coil springs 50 which are disposed about thearmatures and bear upon the frame 6 and the bottom of their respectivelinks 44.

The bias provided by the springs 50 maintains the links in unactuatedposition as shown in full line in FIG. 2 of the drawings. When asolenoid is actuated, for example the solenoid S-4, its armature ispulled in to the body of the solenoid so as to bring the line 44 whichis disposed in the slot 43 of the solenoid armature 42 to the positionshown in dash lines in FIG. 2. Such actuation causes the link 44 topivot about its fulcrum 46 and drive or extend the pin P-4 upwardly sothat the tip of the pin P-4 enters the recessed die 25 and embosses aprotuberance representing the braille code character element in thesheet 1. By virtue of the location of the fulcrums 46 the travel of eachof the links is the same no matter its length or the position of itsactuating solenoid 8-1 to 5-80. The set screws 24 act as stops limitingthe upward travel of the links 44 in response to the bias of the springs50 about the solenoid armatures 42. It will be noted that the fulcrums46 are projections which extend downward from the links into recesses 52in the set screws 47.

The operation of the mechanisms to print lines of braille characters maybe more apparent from FIGS. 1A to IC. The lines of characters 28 to 31have already been embossed or printed on the sheet 1. Consider that thepins P-l to P-80 have been extended to emboss the first row of the nextline 61 of braille characters as shown in FIG. 1A. The sheet 1 is thenadvanced by the tractor mechanism 4 (see FIG. 2) a distance awhich ismeasured for the sake of convenience from the right hand edge of theplate 19; amay be 0.088inch for example. Then the actuating mechanism 8is operated to selectively emboss; the protuberances forming the secondrow 62 of code element of the line of characters 61.

As shown in FIG. 1B, in order to emboss the third row 63 of codeelements, the sheet 1 is advanced another distance aor a total distance2awith the embossing of the row 63 the entire line 61 of braillecharacters is embossed. Then. as shown in FIG. 1C, the sheet 1 isadvanced or fed a double distance (viz., double space) so as to placethe sheet in position for embossing the first row 64 of the next line ofbraille characters. has much as the plate 19 is cut away over the diesection 27 the line of braille characters can be edited, conveniently,by scanning the finger of a person who can read braille across the line.The blind person can thus read the lines of braille characters forediting or other purposes as quickly as they are printed. The mechanismas illustrated in FIGS. 1 to 3, has a relatively small number 7 ofmechanical parts which execute relatively small of braille characters onthe sheet 1 is illustrated in FIGS. 4A and 4B. The timing of the circuitoperations is illustrated by the waveforms shown in FIG. 6, to whichreference should be made as the description of the circuitry proceeds.

The terminal may be provided with its own keyboard 162 or it may receiveserial data in the form of baudot"or selectricbr ascil coded signalsfrom a communication line or other link. The apparatus operates inaccordance with any such digital data messages to provide the lines ofbraille characters on the sheet 1.

Consider the case when the keyboard 162 is used. The keyboard may be anyconventional keyboard which inputs a 7-bit binary code for eachcharacter into a register 160. The keyboard automatically provides aload command to the register 160 whenever a key is depressed. Theregister 160 itself maybe a paralletin/serial-out register. such as anintegrated circuit (IC) that is available from the General InstrumentsCompany as their part AY51010. When data is contained in the register160, abuffer full level enables an AND gate 321 which allows clockpulses from a clock oscillator CLK-l, which is also designated byreference numeral 163, to the shift input of the register 160 forreading our the register. The clock pulses are divided by 2 in atriggerable flip-flop 164 which operates as a divide-by- 2 counter. TheIC 160 is internally provided with a divide-by-eight counter whichaffords the requisite timing. Thus, each character in the keyboard codeis read out through an OR gate 172. The register 160 provides a serialcode for each character consisting ofa start bit, and six data bits. Thestop bits are always levels indicated as being positive voltagerepresenting binary ls and the start of bit level is always indicated bya binary 0, (see Waveform (A), Fig. 6). The serial data from thecommunications line is also made up of multi-bit characters, the firstbit of each character being a binary 0 level. In the case of ascii thereare special control characters which are represented by the value of the6th and 7th bits of the code. In selectric and baudot" codes (baudotbeing the usual teletypewriter code) there are upper case and lower casecharacters. These characters are not embossable and provisions are madein the electronic circuitry for inhibiting the embossing of suchcharacters, as will be described more fully hereinafter. The six bits ofeach character, after the start bit, represent and distinguish theparticular character. it is these bits which are translated or convertedinto braille code characters and used by the system to control theembossing mechanism.

The start bit, whether from the register 160 or from the characterswhich are received from the communication line, are operative to set alatch 200. The latch 200 when set enables an AND gate 340 to pass theCLK-] pulses to a divide-by-l6 counter 205. The output of this counter(viz., the five stages which make up the counter) are decoded in an ANDgate decoder 204 to provide timing pulses TP-9, TP-10, and TP-11 foreach received character.

TP-9 corresponds to the ninth received clock pulse; TP-lO to the tenth;and TP-ll to the eleventh received clock pulse. TP9 is applied as ashift pulse to an input buffer 171. The rate of the CLK-l pulse issufficiently higher than the data rate so that a TP-9 pulse will occurduring the interval of each bit of the coded characters form the line orfrom the register 160.

By the time the eighth advance, as provided by TP-9 shift pulses to theinput buffer 171 occurs, the start bit will be in the first or startstage of the buffer 171 (see Waveform (C), FIG. 6). The start bit isapplied to a delay one-shot 202 which produces a reset pulse RST-l (seeWaveform (G), FIG. 6) which resets the latch 200 and the counter 205thus ending a character timing cycle. Upon occurrence of the start bitand during the time of that bit, the input buffer 171 will be loaded andfull of the data bits of a character.

The six stages of the buffer which contain the six data bits of thecharacter are applied to code converters and 176 for upper and lowercase character respectively. These code converters may be conventionalRead Only Memories (ROMs) which are programmed to convert the binarycodes in the buffer into braille codes having six bits. The lower caseROM 175 also decodes an upper case character by providing an outputlevel on the LC-8 output of the ROM 175. The upper case converter 176decodes a lower case character by providing a UC-8 output. Specialcharacters are decoded by an AND gate 330 which is interconnected to thesixth and seventh stages of the input buffer 171. During the time ofTP-10 and during the start bit time. an AND gate 326 will be enabledwhen UC8 is decoded by the upper case ROM 176. During the same timeperiod and LC-S level from the lower case ROM 175 will enable anotherAND gate 328. Therefore for subsequent lower case characters a latch 324will be set by the output of the AND gate 326 so as to enable the lowercase ROM 175 to provide braille output codes and for subsequent uppercase characters the AND gate 328 will reset the latch 324 thus enablingthe upper case ROM 176 to provide the braille code characters. An ORgate 332 passes either the special character LC-8 or UC-8 levels. andwhen TP-10 occurs, an AND gate 334 will be enabled so'as to set a latch336. The latch 336 when set inhibits an AND gate 211 which otherwisepasses TlP-ll during the start bit period. TP-ll (see Waveform (F), FIG.6) enables a group of AND gates 180, only two of which (for the firstbit of the braille code character) are shown to simplify theillustration. These AND gates pass the braille characters through ORgates 183 to an output buffer 185. Thus when the AND gate 211 isinhibited, as when upper case/ lower case or other special charactersare decoded, there is no readout from the ROMs 175 or 176 and embossingwill not occur.

The reset pulse from the delay one-shot 202 also resets the latch 336and the output buffer at the end of each character reception cycle.

The braille code characters from the output buffer 185 are loaded into apair of parallel-input/serialoutput registers 150 and 151 uponoccurrence of the load pulse (TP-ll) (see Waveform (F), FIG. (6)). Theregisters 150, 151 have their first stage connected to a positive sourceof voltage and their last, or seventh stage, connected to ground so asto be preset to have a binary 1 level start bit in their first stage andbinary 0 level stop bit level in their last stage.

The same load pulse (see Waveform (F), FIG. 6) sets a latch 152. An ANDgate 153 is enabled when the latch 152 is set and allows CLK-2 pulsesfrom a clock oscillator 154 to be applied to the input of fill AND gates155 and 156. The output of the fill AND gate 155 applies shift pulses tothe register 150 for shifting or reading out data out of the register150 into the input of the fortieth character or last register of a firstgroup of buffer registers 158. The AND gate 156 applies shift pulses tothe other register 151 for shifting the characters stored in thatregister into the last orrfortieth character register of a second group159 of output buffer registers. Only one of the AND gates 155 or 156 isenabled depending upon the state of a buffer pointer flip-flop 400.

Tl-Ie output buffer registers 158 and 159 consist of forty seriallyconnected eight-stage shift registers. each corresponding to asuccessive character of the forty characters in a line of charactersthat can be printed by the embossing apparatus illustrated in FIGS. 1 to3. One of the group of registers is filled with forty successivecharacters which are received form the line or from the keyboard 160,converted into braille code characters and stored in one of theparallel-in/serialout registers 150 and 151. The other group ofregisters has the data stored therein read out for the purpose ofoperating the actuating mechanism and printing a line of braillecharacters.

Consider that the pointer flip-flop 400 is set so that its output ishigh. The fill AND gate 156 will then be enabled so as to apply shiftpulses to read out the register 151. The shift pulses are also appliedvia an OR gate 401 to shift data in the forty registers which make upthe output buffer group 159. The registers of the group 159 will befilled one at a time during each received character cycle. It will beappreciated that the CLK-2 oscillator 154 is a high speed clock having arate, say 100 times greater than the CLK-1 oscillator 163. For eachcharacter that is received, converted into braille characters. andstored in the registers 150 and 151, eight CLK-Z pulses are producedbecause a divide by 16 counter 402 counts the CLK-2 pulses. The eighthpulses when counted resets both the counter 402 and the latch 152; thusonly eight shift pulses will be produced upon the reception of eachcharacter. The forty registers in the output buffer group 159 will thenbe filled successively one at a time. When the register group 159 isfilled. the start bit of the first character will be located in thefirst or start bit stage 161 of the first register in the group 159. Abuffer 159 full pulse then appears which is applied via an OR gate 404to trigger the pointer flip-flop 400 which then provides a level whichenables the fill AND gate 155 to shift characters from the register 150into the buffer group 158. The shift pulses for the register group 158are applied via an OR gate 405.

Consider the case where the buffer group 158 has just filled with fortycharacters and a buffer 158 full level is obtained from the first orstart stage of the first character register of the group 158. The buffer158 full signal is applied via an OR gate 406 to set an emboss cycleflip-flop 407. When set, the flip-flop 407 enables an AND gate 408 topass CLK-3 pulses from a clock oscillator 409. The repetition rate ofthe CLK-3 pulses may be approximately equal to or slightly less than theCLK-l pulse rate. When the flip-flop 407 is set it initiates anembossing'cycle. The timing of embossing operations during the cycle iscontrolled by a divide by 16 counter 413. The five stages of thatcounter are connected to an AND gate decoder 410 which provides outputson the first, fifth, ninth and thirteenth of the CLK-3 clock pulseswhich are counted by the counter 413. The decoder 410 thus provides fourtiming pulses, TP-l, TP-S, TP-9, and TP-l3. The first three pulses,TP-l, -5, and -9 are applied via an OR gate 411 to trigger a one-shot412 which provides three embossing pulses of sufficient time durationduring the embossing cycle (viz., the period during which the embosscycle 8 flip-flop 407 is set) (see Waveform (.1), FIG. 6). The

one-shot 412 may be adjusted so as to adjust the embossing pulseduration (see Waveform (K)) to accommodate for the travel of thesolenoid armatures 42, link 44 and pins P-l to P- (see FIGS. 1 to 3). Anapproximately thirty millisecond embossing pulse from the flipflop 412has been found suitable for an embossing rate of lines of braillecharacters per minute.

The embossing pulse passes through an AND gate 414 which is enabled whenthe pointer flip-flop is set. This AND gate 414 is referred to as theembossing AND gate. It will be noted that another embossing AND gate 416is provided for passing embossing pulses when the pointer flip-flop 400is reset (Q hight). Each embossing pulse passes through the OR gate 405for shifting or advancing the bits in each of the forty characterregisters of the buffer group 158. There are three embossing pulses percycle (viz., corresponding to TP-l, -5 and -9). During each pulse perioda pair of braille code elements will be embossed. As explained above,the braille code is made up of six elements in three pairs. Aside fromthe start and stop bits there are six bits stored in each of the fortycharacter registers of the buffer group 158. The first and fourth bitsin the register, the second and fifth bits in the register and the thirdand sixth bits in the register, respectively, correspond to each of thethree pairs of braille code elements per character. By reading out thefirst and fourth stages of each of the character registers in the fortyregisters which make up the buffer group 158, signals representing eachpair of braille code elements can be provided.

A pair of AND gates R-l, R-2, forty pairs in all, are respectivelyinterconnected to the first and fourth stages of each of the fortycharacter records to the buffer group 158. These gates are enabled bythe embossing pulses which are applied thereto via a second embossingAND gate 420. The leading edge of the embossing pulse which is appliedto the shift inputs of the character registers of th buffer group 158advances the data in the forty registers. The rest of the embossingpulse enables the AND gates R-1 and R-2. Thus on the first embossingpulse (tp-l) the first and fourth bits of each braille character will beadvanced into the first and fourth stages of the character registers ofthe buffer group 158, and the AND gates R-1, R-2 will be enabled. Outputpulses are then applied forty pairs of output OR gates R-3, R-4. Ofcourse, pulses will not be passed through the AND gates R-l, R-2 if thebits in the register are binary 0 bits. THe outputs of the OR gates areapplied via driver amplifiers R-5, R-6 to the operating windings of thesolenoids 8-1 to 5-80. Alternatively, the output amplifier pairs R-5,R-6 may be inverters, which when the output of the OR gates R-3, R4 arehigh, provide a low level at their outputs so as to permit current topass through the operating windings of the selenoids 8-1 to S-80 fromsources of operating voltage indicated at +V.

In this manner a row consisting of forty pairs of braille code elementsis simultaneously printed on the sheet 1 (FIGS. 1 to 3). The sheet isadvanced one space (distance 0, FIGS. 1A to IC) upon the trailing edgeof each embossing pulse. The trailing edge of each pulse triggers aone-shot 421 which provides an output pulse (see Waveform (L), FIG. 6)immediately after each embossing pulse. The one-shot 421 output pulsepasses through an OR gate 422 and triggers another one-shot 423 whichprovides a paper advance motor drive pulse (Waveform (M)), which may forexample be 20 milliseconds in duration to allow a paper movement of0.088 inch. this pulse is applied to a paper advance motor 424 via adrive amplifier 425. The paper advance motor is mechanically coupled tothe sprocket of the pin tractor 4 (FIG. 2) and advances the sheet 1 bythe distance a (.088). The sheet is then in position to receive thesecond row of braille character elements.

The second embossing pulse TP- then advances bits two and five of thebraille characters into the first and fourth stages of the characterregisters of the buffer group 158. Embossing and paper feed then occursas was the case for the first pair of braille character elements in thefirst row. The sheet is then advanced into position to receive the thirdrow of braille element pairs. The third embossing pulse TP-9 thenadvances the third and sixth braille character code elements into thefirst and fourth stages of the register. Embossing then occurs as wasthe case for the first and second row of braille character elementpairs.

The next timing pulse from the decoder is the TP-13 pulse (see Waveform(N)). That pulse resets the counter 413 ending the embossing cycle. Italso is applied via the OR gate 422 to trigger the one-shot 423 andproduces a second paper advance (thus after printing the third row ofcharacters there are two paper advances, one due to the TP-9 and theother due to the TP-13 pulses from the decoder 410. The sheet is now inposition to receive the next line of braille characters (see FIG. 1C).The next or successive line of charcters are read out of the buffergroup 159 which has been filling with characters while the charactersstored in the buffer group 158 were being read out and used to operatethe embossing mechanism. The TP-l3 pulse also passes through an AND gate427 which is enabled by the Q output of the pointer flip-flop 400. ITWill be recalled that the Q output of the pointer flip-flop 400 is highduring an embossing cycle when the buffer group 158 is read out. TheTP-13 pulse then resets the registers in the buffer group 158. Thebuffer group 159 has an embossing AND gate 430 and a reset AND gate 431which operates when the buffer group 159 is read out during itsembossing cycle.

The buffer group 159 also has associated with the first and fourthstages of each of its character registers, a pair of AND gates R-7, R-8which serves the same purpose as the AND gate pairs R-l, R-2 forproviding embossing signals via and OR gates R-3, R-4 to the solenoid8-1 to 8-80 operating windings. After each embossing cycle the TP-13pulse resets the emboss cycle flip-flop 407 to terminate the cycle.

In the event that it is desired to emboss partial lines rather than fulllines and alternate path for CLK-2 pulses to the AND gates 155 and 156may be provided via another AND gate (not shown). When less than fortycharacters per line are desired a flip-flop (not shown) may be set, sayby a button such as the character return key on th keyboard 162. Thebuffer full signal from the first character register stages may beapplied to reset the flip-flop. When set, the flip-flop enables the ANDgate in the alternate pair to apply.

From the foregoing description it will be apparent that there has beenprovided an improved braille communications terminal or typewriter whichis capable of printing or embossing braille characters a line at a timeand thus provides extremely high speed brail-ling operations. Variationsand modifications in the herein described embodiment of the inventionwill undoubtedly suggest themselves to those skilled in the art.Accordingly the foregoing description should be taken merely asillustrative and not in any limiting sense.

Whatt is claimed is:

1. Braille communications apparatus which comprises:

a. means including a collinear row of embossing elements grouped in aplurality of pairs for embossing the collinearly disposed code elementsin a line of braille code characters on a sheet, and

b. means coupled to each of said embossing elements and responsive tocode signals representing said characters for successively operatingsaid embossing means to emboss on each of said successive operationssuccessive entire lines of said braille code elements until an entireline of braille code characters is formed.

2. The invention as set forth in claim 1 wherein said embossing meansincludes means for advancing said sheet to present lines on said sheetwhich have a first displacement from each other between the lines ofcollineraly disposed code elements in each line of braille characters,which lines of elements are embossed on each advance until the line ofcode characters is formed, and second displacement greater than saidfirst displacement between successive lines of braille characters.

3. The invention as set forth in claim 1 wherein said embossing meanscomprises a row of pins each corresponding to a different braillecharacter code element, and means for reciprocating said pins into andout of embossing relationship with said sheet.

4. The invention as set forth in claim 3 wherein different pairs of saidpins are laterally offset from each other in said row for embossingsuccessive pairs of code elements of different braille code charactersin each said line of braille code characters.

5. The invention as set forth in claim 4 including a member havng aplurality of pairs of recessed dies corresponding to said pins anddisposed in a row, said member being disposed opposite to said pins andspaced therefrom to permit said sheet to pass therebetween, and withsaid dies aligned with their corresponding pins.

6. The invention as set forth in claim 5 further comprising a pluralityof electromechanical actuators each for a different one of said pins.

7. The invention as set forth in claim 6 wherein pairs of said pluralityof actuators are provided for each of said pairs of pins, each of saidactuators in each of said pairs being disposed on an opposite side ofsaid row of pins.

8. The invention as set forth in claim 6 wherein each of said actuatorsincludes a solenoid, and a link pivotally mounted intermediate the endsthereof and extending between said solenoid on the one of said pinsactuated by said solenoid.

9. The invention as set forth in claim 8 including spring means forbiasing each of said pins away from said sheet, said bias being overcomeby said solenoid when actuated to advance said pin into embossingrelationship with the sheet.

10. The invention as set forth in claim 9 wherein said solenoids aredisposed in rows parallel to said row of pins and on opposite sides ofsaid row of pins, and wherein said links extend perpendicularly to saidrow of pins.

11. The invention as set forth in claim 10 wherein said rows ofsolenoids are offset at different distances form said row of pins, saidlinks being of different length corresponding to the distance betweentheir respective solenoids and the pins actuated thereby, and aplurality of members each defining a fulcrum on which said links areseparately pivotally mounted, said fulcrum members being disposed inrows parallel to said row of pins and offset from said pin rows bydifferent distances in accordance with the lengths of the links pivotedthereon whereby said links have substantially equal travel paths whenactuated by their respective solenoids.

12. The invention as set forth in claim 2 wherein said advancing meanscomprises a pin tractor mechanism adapted to engage holes disposed alongthe edge of said sheet, and an electromagnetic actuator for providingstepwise movement of said pin tractor mechanism for electively feedngsaid shee '1 distance corresponding to the separation of on plurality ofbraille character code element lines.

13. The invention as set forth in claim 1 wherein said operating meanscomprises means for receiving code signals representing successivecharacters,

means having storage for a plurality of said characters which areadapted to constitute a line of braille characters, and

means for reading out said storage means a plurality of times, each timeto read out simultaneously all of the signals corresponding to thecollinearly disposed elements in said line of braille characters.

14. The invention as set forth in claim 13 wherein said storage meanscomprises a plurality of registers each for a successive one of saidbraille characters, each of said registers having a plurality of stageswhich provide storage for code signals correponding to different ones ofthe code elements of said braille characters, and means for successivelyreading out of said registers the different pairs of said code signals,each of said pairs corresponding to a collinearly disposed pair of codeelements of a braille character whereby the collinearly disposed codeelements in each line of element constituting a line of braille elementsare presented for operating said embossing means.

15. The invention as set forth in claim 14 wherein said embossing meanscomprises a separate pair of pins for embossing each of said pairs ofcode elements, said pins being disposed in a row extending across thesheet,

and electromagnetic means for actuating said pins into embossingrelationship with said sheet, said operating means further comprisingmeans responsive to each of said different pairs of code signals readout of said registers for operating said actuating means for each ofsaid separate pairs of pins.

16. The invention as set forth in claim 15 including means for feedingsaid sheet upon each read-out of said pairs of code signals and theembossing of line of said braille code character elements in responsethereto.

17. The invention as set foth in claim 16 including means for operatingsaid feeding means for feeding said sheet a distance greater than thedistance said sheet is fed after read-out of a line of said braille codecharacter elements when a plurality of said pairs of said code signalsconstituting an entire braille character are read out of said registers.

18. The invention as set forth in claim 14 wherein said registerread-out means comprises means for simultaneously reading the codesignals stored in two of the stages of said registers, and means forshifting said code signals through said register stages a plurality oftimes, each such shifting providing a successive pair of said codesignals for read-out, and means responsive to said shifting means foroperating said embossing means in response to each of said successivepairs of code signals.

19. The invention as set forth in claim 18 further comprising meansincluded in said receiving means for converting said code signalsrepresenting each of said characters into braille character codesignals, and means for entering said braille character code signalsserially into said registers.

20. The invention as set forth in claim 19 wherin said registerscomprise a plurality of groups of registers each having storage for aplurality of said braille character code signals equal in number to thenumber of said braille characters adapted to be embossed in each of saidlines of braille characters, and means operative when the one of saidregisters in one of said plurality of groups which has storage for thebraille character to be embossed at the beginning of the line is fullfor operating said reading out means for reading out said full registerin said one register group while enabling another of said plurality ofregister groups to receive additional braille character code signalswhereby successive lines of said braille characters corresponding tobraille character code signals stored in differnt ones of said registergroups are embossed on said sheet.

1. Braille communications apparatus which comprises: a. means includinga collinear row of embossing elements grouped in a plurality of pairsfor embossing the collinearly disposed code elements in a line ofbraille code characters on a sheet, and b. means coupled to each of saidembossing elements and responsive to code signals representing saidcharacters for successively operating said embossing means to emboss oneach of said successive operations successive entire lines of saidbraille code elements until an entire line of braille code characters isformed.
 2. The invention as set forth in claim 1 wherein said embossingmeans includes means for advancing said sheet to present lines on saidsheet which have a first displacement from each other between the linesof collineraly disposed code elements in each line of braille charactes,which lines of elements are embossed on each advance until the line ofcode characters is formed, and second displacement greater than saidfirst displacement between successive lines of braille characters. 3.The invention as set forth in claim 1 wherein said embossing meanscomprises a row of pins each corresponding to a different braillecharacter code element, and means for reciprocating said pins into andout of embossing relationship with said sheet.
 4. The invention as setforth in claim 3 wherein different pairs of said pins are laterallyoffset from each other in said row for embossing successive pairs ofcode elements of different braille coDe characters in each said line ofbraille code characters.
 5. The invention as set forth in claim 4including a member havng a plurality of pairs of recessed diescorresponding to said pins and disposed in a row, said member beingdisposed opposite to said pins and spaced therefrom to permit said sheetto pass therebetween, and with said dies aligned with theircorresponding pins.
 6. The invention as set forth in claim 5 furthercomprising a plurality of electromechanical actuators each for adifferent one of said pins.
 7. The invention as set forth in claim 6wherein pairs of said plurality of actuators are provided for each ofsaid pairs of pins, each of said actuators in each of said pairs beingdisposed on an opposite side of said row of pins.
 8. The invention asset forth in claim 6 wherein each of said actuators includes a solenoid,and a link pivotally mounted intermediate the ends thereof and extendingbetween said solenoid on the one of said pins actuated by said solenoid.9. The invention as set forth in claim 8 including spring means forbiasing each of said pins away from said sheet, said bias being overcomeby said solenoid when actuated to advance said pin into embossingrelationship with the sheet.
 10. The invention as set forth in claim 9wherein said solenoids are disposed in rows parallel to said row of pinsand on opposite sides of said row of pins, and wherein said links extendperpendicularly to said row of pins.
 11. The invention as set forth inclaim 10 wherein said rows of solenoids are offset at differentdistances form said row of pins, said links being of different lengthcorresponding to the distance between their respective solenoids and thepins actuated thereby, and a plurality of members each defining afulcrum on which said links are separately pivotally mounted, saidfulcrum members being disposed in rows parallel to said row of pins andoffset from said pin rows by different distances in accordance with thelengths of the links pivoted thereon whereby said links havesubstantially equal travel paths when actuated by their respectivesolenoids.
 12. The invention as set forth in claim 2 wherein saidadvancing means comprises a pin tractor mechanism adapted to engageholes disposed along the edge of said sheet, and an electromagneticactuator for providing stepwise movement of said pin tractor mechanismfor electively feedng said sheet a distance corresponding to theseparation of one or a plurality of braille character code elementlines.
 13. The invention as set forth in claim 1 wherein said operatingmeans comprises means for receiving code signals representing successivecharacters, means having storage for a plurality of said characterswhich are adapted to constitute a line of braille characters, and meansfor reading out said storage means a plurality of times, each time toread out simultaneously all of the signals corresponding to thecollinearly disposed elements in said line of braille characters. 14.The invention as set forth in claim 13 wherein said storage meanscomprises a plurality of registers each for a successive one of saidbraille characters, each of said registers having a plurality of stageswhich provide storage for code signals correponding to different ones ofthe code elements of said braille characters, and means for successivelyreading out of said registers the different pairs of said code signals,each of said pairs corresponding to a collinearly disposed pair of codeelements of a braille character whereby the collinearly disposed codeelements in each line of element constituting a line of braille elementsare presented for operating said embossing means.
 15. The invention asset forth in claim 14 wherein said embossing means comprises a separatepair of pins for embossing each of said pairs of code elements, saidpins being disposed in a row extending across the sheet, andelectromagnetic means for actuating said pins into embossingrelationship with said sheet, saiD operating means further comprisingmeans responsive to each of said different pairs of code signals readout of said registers for operating said actuating means for each ofsaid separate pairs of pins.
 16. The invention as set forth in claim 15including means for feeding said sheet upon each read-out of said pairsof code signals and the embossing of line of said braille code characterelements in response thereto.
 17. The invention as set foth in claim 16including means for operating said feeding means for feeding said sheeta distance greater than the distance said sheet is fed after read-out ofa line of said braille code character elements when a plurality of saidpairs of said code signals constituting an entire braille character areread out of said registers.
 18. The invention as set forth in claim 14wherein said register read-out means comprises means for simultaneouslyreading the code signals stored in two of the stages of said registers,and means for shifting said code signals through said register stages aplurality of times, each such shifting providing a successive pair ofsaid code signals for read-out, and means responsive to said shiftingmeans for operating said embossing means in response to each of saidsuccessive pairs of code signals.
 19. The invention as set forth inclaim 18 further comprising means included in said receiving means forconverting said code signals representing each of said characters intobraille character code signals, and means for entering said braillecharacter code signals serially into said registers.
 20. The inventionas set forth in claim 19 wherin said registers comprise a plurality ofgroups of registers each having storage for a plurality of said braillecharacter code signals equal in number to the number of said braillecharacters adapted to be embossed in each of said lines of braillecharacters, and means operative when the one of said registers in one ofsaid plurality of groups which has storage for the braille character tobe embossed at the beginning of the line is full for operating saidreading out means for reading out said full register in said oneregister group while enabling another of said plurality of registergroups to receive additional braille character code signals wherebysuccessive lines of said braille characters corresponding to braillecharacter code signals stored in differnt ones of said register groupsare embossed on said sheet.